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191.
In the product of carbon made from tar oil by plasma pyrogenation, some nanowires, whose diameter is 9~20 nm and whose length is 300 nm were found. The result of X-ray Energy Dispersed Spectrum (EDS) indicated that it is a new compound K2Ti8O15, which has never been reported before. Compared with the corresponding stoichiometry compound K2Ti8O15, it is a non-stoichiometry compound in which two oxygen atoms are absent. It is due to the fact that the intensive deoxidization occured in the experimental process and the valence of titalium is alterable. Its microstructure in detail by high revolution electromicroscopy (HREM) and X-ray diffraction were studied. 相似文献
192.
Guang Peng Zhou Yong Hai Hui Ning Ning Wan Qiu Ju Liu Zheng Feng Xie Ji De Wang 《中国化学快报》2012,23(6):690-694
A series of novel Schiff bases bearing triazole structure were synthesized and characterized by IR and NMR.Mn(OAc)2/Schiff base efficiently catalyzed Henry reaction of nitroalkanes with aldehydes to produce the corresponding products of β-nitroalcohols, under mild conditions with high yields(up to 99%).A reaction mechanism is proposed based on the experimental results. 相似文献
193.
Xue Bai Wan Qi Shi Hua Feng Chen Ping Zhang Ying Li Shu Fan Yin 《Chemistry of Natural Compounds》2012,48(1):60-65
New 4-chalcone ursolate and 1-acetyl-3-(4-phenyl)-4,5-dihydro-2-pyrazoline-5-phenyl ursolate derivatives were synthesized
by esterification of UA and chalcone or pyrazoline. The compounds were structurally confirmed by IR, 1H NMR, 13C NMR, and HR-MS spectroscopy. The cytotoxicity of ten derivatives was evaluated against A549, SKOV3, and HepG2 cell lines
by MTT assay. The result showed that several compounds were more potent than UA against A549 and SKOV3 cells; however, none
of them were more potent than UA against HepG2. 相似文献
194.
195.
Dr. Nuo‐Wei Zhang Prof. Chuan‐Jing Huang Xiao‐Quan Zhu Jing‐Dong Xu Prof. Wei‐Zheng Weng Prof. Hui‐Lin Wan 《化学:亚洲杂志》2012,7(8):1895-1901
The effects of calcination temperature and feedstock pretreatment on the catalytic performance of Co/γ‐Al2O3 catalysts were studied for partial oxidation of methane (POM) to synthesis gas, with emphasis on the role of feedstock pretreatment. The physicochemical properties of the catalysts were characterized by N2 adsorption, X‐ray diffraction (XRD), transmission electron microscopy (TEM), H2 temperature‐programmed reduction (H2‐TPR), and Raman spectroscopy. The results showed that the pretreatment of the catalyst by reaction gas significantly improved the catalytic activity and stability for the POM reaction. On the other hand, the effect of calcination temperature was less significant. Although the initial activity was increased by an increased calcination temperature, the catalyst without the feedstock pretreatment suffered a rapid deactivation. The reaction‐atmosphere pretreatment was revealed as a process that mainly modified the surface structure of the catalyst. In that process, the formation of a CoAl2O4‐like compound led to high Co metal dispersion after reduction, and the transformation of the carrier into α‐Al2O3 occurred over the catalyst surface. Both the high dispersion of cobalt and the presence of α‐Al2O3 surface phase were assumed as the important factors resulting in an excellent catalytic performance in terms of high activity and high stability. 相似文献
196.
水中铬污染治理的研究进展 总被引:6,自引:0,他引:6
综述了水中铬污染治理的研究进展,包括物理法、物理化学法、化学法、电化学法和生物处理法,并分别评述了各种处理方法的优缺点,提出了未来含铬废水治理的发展方向。 相似文献
197.
198.
Xian‐Kai Wan Shang‐Fu Yuan Zhi‐Wei Lin Prof. Dr. Quan‐Ming Wang 《Angewandte Chemie (International ed. in English)》2014,53(11):2923-2926
The chirality of a gold nanocluster can be generated from either an intrinsically chiral inorganic core or an achiral inorganic core in a chiral environment. The first structural determination of a gold nanocluster containing an intrinsic chiral inorganic core is reported. The chiral gold nanocluster [Au20(PP3)4]Cl4 (PP3=tris(2‐(diphenylphosphino)ethyl)phosphine) has been prepared by the reduction of a gold(I)–tetraphosphine precursor in dichloromethane solution. Single‐crystal structural determination reveals that the cluster molecular structure has C3 symmetry. It consists of a Au20 core consolidated by four peripheral tetraphosphines. The Au20 core can be viewed as the combination of an icosahedral Au13 and a helical Y‐shaped Au7 motif. The identity of this Au20 cluster is confirmed by ESI‐MS. The chelation of multidentate phosphines enhances the stability of this Au20 cluster. 相似文献
199.
Lysosomal pH Rise during Heat Shock Monitored by a Lysosome‐Targeting Near‐Infrared Ratiometric Fluorescent Probe 下载免费PDF全文
Dr. Qiongqiong Wan Prof. Dr. Suming Chen Prof. Dr. Wen Shi Lihong Li Prof. Dr. Huimin Ma 《Angewandte Chemie (International ed. in English)》2014,53(41):10916-10920
Heat stroke is a life‐threatening condition, featuring a high body temperature and malfunction of many organ systems. The relationship between heat shock and lysosomes is poorly understood, mainly because of the lack of a suitable research approach. Herein, by incorporating morpholine into a stable hemicyanine skeleton, we develop a new lysosome‐targeting near‐infrared ratiometric pH probe. In combination with fluorescence imaging, we show for the first time that the lysosomal pH value increases but never decreases during heat shock, which might result from lysosomal membrane permeabilization. We also demonstrate that this lysosomal pH rise is irreversible in living cells. Moreover, the probe is easy to synthesize, and shows superior overall analytical performance as compared to the existing commercial ones. This enhanced performance may enable it to be widely used in more lysosomal models of living cells and in further revealing the mechanisms underlying heat‐related pathology. 相似文献
200.
Ka Wan Li Patricia Klemmer August B. Smit 《Analytical and bioanalytical chemistry》2010,397(8):3195-3202
The brain integrates complex types of information, and executes a wide range of physiological and behavioral processes. Trillions of tiny organelles, the synapses, are central to neuronal communication and information processing in the brain. Synaptic transmission involves an intricate network of synaptic proteins that forms the molecular machinery underlying transmitter release, activation, and modulation of transmitter receptors and signal transduction cascades. These processes are dynamically regulated and underlie neuroplasticity, crucial to learning and memory formation. In recent years, interaction proteomics has increasingly been used to elucidate the constituents of synaptic protein complexes. Unlike classic hypothesis-based assays, interaction proteomics detects both known and novel interactors without bias. In this trend article, we focus on the technical aspects of recent proteomics to identify synapse protein complexes, and the complementary methods used to verify the protein–protein interaction. Moreover, we discuss the experimental feasibility of performing global analysis of the synapse protein interactome. 相似文献